Construction machine equipped with battery

A construction machine comprising:

• a battery;
• a controller that is operated by supply of power from the battery;
• a key switch that is connected to the controller and switched between a key-off state of providing the controller with an instruction to halt an engine and a key-on state of providing the controller with no instruction to halt the engine;
• an interruption switch that is switched between a supply allowing state of allowing supply of power from the battery to the controller and a supply interruption state of interrupt supply of power from the battery to the controller, the interruption switch being disposed outside a cab of the construction machine and allowing an operator to manually shut off supply of power;
• a sensor that detects presence/absence of interruption necessary motion which is a motion necessary for manipulating the interruption switch;
• an alarm device capable of issuing an alarm;
• and
• an alarm control device that causes the alarm device to issue the alarm only when a condition that the key switch is in the key-off state, a condition that the interruption switch is in the supply allowing state, a condition that the controller is being operated, and a condition that the sensor has detected presence of the interruption necessary motion are all satisfied,
• wherein the state of the key switch and the state of the interruption switch are independently changeable.